THE RETREATING MONSOON : THE RETREATING MONSOON
Retreating Monsoon - Meaning : Retreating Monsoon - Meaning Strength of monsoon decreases
Extent to which monsoons were able to reach from June to September decreases
Direction remains the same
Also called ‘Retreating SW Monsoon’
Retreating Monsoon - Causes : Retreating Monsoon - Causes Sun moves from Equator towards Tropic of Capricorn
Temperatures drop
LP replaced by HP
Retreating Monsoon - Dateline : Retreating Monsoon - Dateline October and November
Monsoon withdrawal dates
Northern Plains – 15th September
Western Ghats – 1st October
Kolkata – 15th October
Kerala – 15th November
Slide 5 : MECHANISM OF RETREATING MONSOON
Retreating Monsoon - Summary : Retreating Monsoon - Summary Monsoons decrease in intensity
LP gradually replaced by HP
In the northern plains, it is oppressively hot – a condition called ‘October Heat’
Cyclones hit east coast and Bangladesh
Kerala last state from where monsoons withdraw
WINTERS OF INDIA : WINTERS OF INDIA
The Indian Winter - Dateline : The Indian Winter - Dateline November to February
Sun descends towards Tropic of Capricorn
Slide 9 : Temperatures in winter 10 – 15o C 25o C 5o C 30o C
Slide 10 : Pressure in winter HP LP LP
WINDS IN WINTER : WINDS IN WINTER Although India lies in Trade Wind Belt,
Himalayas & Arakan Yoma Ranges do not allow them to come to India
WINDS IN WINTER : WINDS IN WINTER HP over Land, LP over Sea
Winds move from Land to Sea
Deflected due to Coriolis Effect
Blow from NE to SW
Called NE monsoon winds
Direction coincides with Trade Winds
SW Monsoon winds ‘reverse’ in direction
WINDS IN WINTER : WINDS IN WINTER
Slide 14 : PRESSURE BELTS IN SUMMER
Slide 15 : PRESSURE BELTS IN WINTER
RAINFALL IN WINTER : RAINFALL IN WINTER Warm and cold fronts meet Cause cyclonic rainfall in Punjab
Slide 17 : Westerlies move along foothills of Himalayas ….enter the Bay of Bengal
Slide 18 : …shed moisture over Tamil Nadu
Summary of Indian Winter : Summary of Indian Winter Cool and Pleasant
December to February
Sun shines in the Southern Hemisphere
HP over land; LP over Sea
Winds move from Land to Sea (North East Monsoons) – a phenomenon called ‘Reversal of Winds’
Summary of Indian Winter : Summary of Indian Winter Western Disturbances come to India
Cause cyclonic rainfall in Punjab
Move along the foothills of the Himalayas into the Bay of Bengal
NE Monsoons joined by Western Disturbances cause rainfall in Tamil Nadu (Palni, Javadi and Shevaroy hills)